Wax eliminator



Aug- 27 l929- E. A. DONALDSON 1,726,345

- AWAX ELIMINATOR Filed May 9. 1927 Fig. 1

EV.A. Donaldson 51H0: un:

Patented Aug. 27, 1929.

UNiTED STATES EDWIN A. DONALDSON, OF LINCOLN, NEBRASKA.

WAX ELIMINATOR. y

Application 'filed May 9, 1927.

My invention relates to burners and more specifically to burners of the kinds which are especially adapted for use in dental laboratories.

The primary object of my invention 1s the provision of a burner which will combine the utility of the burners of two or more kinds at present in use in dental laboratories.

Another important object of my invention is the provision of a burner which will eX- peditiously, uniformly and thoroughly elnninate wax from dental casting cases.

A third object of my invention is the provision of a device which may be used as 'an' ordinary Bunsen burner for sterilizing 1nstruments, soldering or any of the other various operations performed by the use of a Bunsen burner.

Having in view these objects and others which will be pointed out in the following description, I will now refer to the drawings, in which- Figure 1 is a view, partly in median longitudinal section, of all of the parts of my burner.

Figure 2 is a view in perspective of the cap or plate constituting the part of my burner, the cap or plate being used when it is desired to eliminate wax from dental casting cases.

The Bunsen burner itself comprises a base 10, a vertical gas and air passage 11, a gas inlet 12 with a nipple 13 for convenience in attaching a rubber tube, and an air inlet 14C. All of this construction is common to Bunsen burners.

In carrying out my invention I provide the upper end of the tube 11 with an external screw thread and secure thereto a pan 15.

16 having an annular ledge at its upper an inner edge. It should be noted that the upper end of the tube 11 extends slightly above the inner bottom surface of the pan. The construction thus far described may be used as an ordinary Bunsen burner and the pan in this case will serve to catch wax drippings and the like and to evaporate them. Since the upper end of the tube 11 is above the bottom surface of the pan, the drippings are not allowed to enter the passageway in the tube 11 and to thus clog it up.

The cap 17 as shown in Figure 2- includes a disc-like portion which may be seated on the ledge of the flange 16 and includes also a raised central portion. This cap is provided sible for any drippings This aan has an upstandino peripheral flanOe l t 2Da that the inlay is Serial No. 190,079.

with a. plurality of apertures 18 in annular series surrounding the raised portion but spaced slightly therefrom. l/Vhen the cap 17 is placed in position above the burner and t-he jets of gas from the apertures 18 are ignited, the burner may be used for driving out or eliminating Wax and moisture from dental casting cases.

The burner may be used Without the cap for sterilizing instruments, warming wax, and for any of the other numerous uses to which the open flame of the'Bunsen' burner is putin dental work. The pan 16 is warmed by the flame so that any drippings in the pan are immediately vaporized and driven oft. Since the upper end of the tube 11 extends above the inner bottom surface of the pan, it is imposto enter the tube 11 to clog the pasasge of the gas.

The lid is designed primarily for use in eliminating wax from dental castings. In making these castings, a waX impression is first made of the cavity in the tooth and this wax impression is imbedded in wet plaster which is packed into a tubular metal case, there being a minute sprue hole leading to the wax impression. The wax is then removed from the plaster through the sprue hole after which the cavity is filled with gold or other suitable metal. If this work is properly done, the metal casting will be of the eX- act size and shape of the cavity in the tooth. The wax is usually removed from the plaster by heating it and thus driving off the wax through the sprue hole. In the usual processes of removing the wax, there has been more or less dihculty in securing an even iiame and evenly distributed about the casting case with the result that tiny particles of wax have been left in the plaster with the result a poorly fitting inlay. This difliculty is avoided by the use of my waX eliminator. The lid is seated on the pan and the gas is ignited as it emerges through the orifices 18 and the casting case is placed on the raised portion 17 of the lid with its sprue hole directed downwardly. The jets of flame from the orifices 18 are drawn inwardly and this effect is accentuated by the vertical wall of the raised portion 17. The entire casting case is thus subjected to very evenly distributed heat on all of its vertical sides. The moisture in the plaster is quickly brought to the boiling point and the flame is then increased so that the steam generated vwithin the plaster forces the wax out through the In a dental burner, a Bunsen burner, a pan sprue hole against the top surface of the raised portion 17. The entire lid is kept hot by the ame and any wax which lows out against the upp-er surface or" the lid is instantly vaporized. The result is a plaster cast having a cavity from which the waX is thor` oughly eliminated so that the cavity is an eX- act duplicate of the cavity in the tooth from which the wax impression has been made.

Having thus described my invention in such full, clear, and exact terms that its construction and operation will be readily understood by others skilled in the art to which it pertains, what I claim as new and desire to secure by Letters Patent of the United States surrounding said Bunsen burner at its upper extremity and concentric therewith, the upper edge of the vertical wall of said pan being stepped, and a removable lid seated in the upper edge of the vertical wall of said pan, said lid being provided with a centrally thickened portion having a vertical wall of cylindrical form and being also provided with a plurality of circularly arrr nged and vertically directed orifices spaced from the cylindrical wall of said thickened portion, the arrangement being` such that the heat in the centrally thickened portion will induce a central upward draft to thereby cause the Haine jets from all or' the orifices to be deflected in-v wardly toward the center' of the upper surface of said centrally thickened portion.

In testimony whereof I aiiix my signature.

EDWIN A. DONALDSON. 

